The invention relates to a semiconductor device and its manufacturing technique and particularly, to a technique which is effectively applied to a semiconductor device and its manufacturing technique, for example, including a light receiving element (light receiver) having a photoelectric conversion function.
Japanese Unexamined Patent Application Publication No. Hei 10 (1998) -290023 describes a technique for forming an N-type germanium layer, a germanium single crystal layer, a P-type germanium layer, and a P-type silicon layer, within a groove formed in the N-type epitaxial layer.
In “High Performance Silicon Waveguide-Integrated PIN and Schottky Ge Photodiodes and their Link with Inverter-Type CMOS TIA Circuits” Extended Abstracts of the 2013 International Conference on Solid State Devices and Materials, Fukuoka, 2013, pp 980-981, written by J. Fujikata, M. Noguchi, M. Miura, D. Okamoto, T. Horikawa, and Y. Arakawa, there are described a PIN Ge photodiode and a Schottky Ge photodiode including a p+ ntype silicon layer formed on a silicon substrate through an embedded insulting layer, a germanium layer formed on the p+ type silicon layer, an n+ type silicon germanium layer (or non-doped silicon germanium layer) formed on the germanium layer.